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From: scm@datlog.co.uk ( Steve Mawer )
Newsgroups: comp.lang.c
Subject: Re: Something new in C syntax
Summary: Something new, something old
Keywords: ifdefs comments
Message-ID: <1734@dlvax2.datlog.co.uk>
Date: 3 Feb 89 08:28:33 GMT
References: <4586@bunker.UUCP>
Reply-To: scm@datlog.co.uk ( Steve Mawer )
Organization: Data Logic Ltd, Queens House, Greenhill Way, Harrow, London.
Lines: 39

In article <4586@bunker.UUCP> allen@bunker.UUCP (C. Allen Grabert) writes:
>                                                     I did not write the
>code, but thought, like the author, that the first "printf" should not
>have been commented out.
>
>main()
>{
>#ifdef jjj
>/*
>#endif
>	printf("hello world\n");
>#ifdef jjj
>*/
>#endif
>	printf("goodbye cruel world\n");
>}


If you've ever looked at the output from
the C compiler's preprocessor (on every
system *I've* seen, anyway) you'll find
that all comment lines are replaced with
blank lines.

(The whitespace from #included files has
to be seen to be believed :-)).

That being the case, it's the preprocessor
that handles the comments, so the lines upto,
but exluding, the last #endif, will be
blanked.  This may be confusing but it's
predictable (and expected?).




-- 
Steve C. Mawer        <scm@datlog.co.uk> or < {backbone}!ukc!datlog!scm >
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